Low vaccination rates trigger fears

Parts of Oregon, Washington state, Idaho, Montana and a few other states have some of the lowest rates of compliance with vaccination guidelines—and the problem is growing, health officials say. Overall vaccination rates in some of these communities are under 80%, far below the threshold that is needed to prevent an outbreak for certain diseases. Exemptions in many states for philosophical or religious reasons allow parents to opt out of requirements for children to be vaccinated before entering school. Other parents delay immunizations for their young children, leaving them exposed to possible infections for a longer time.